NOTCam commissioning - imaging mode ------------------------------------ Referring to my NOTCam Commissioning Plan (imaging mode) from September 16th 2002, I here give a short update of the status. -------------------------------------------------------------------------- 1. The Detector - pick-up noise problem solved - readout time too long TBD (CUO) - gain & readnoise both modes found & monitored regularly - dark current will be monitored from now on - non-linearity found & monitored regularly - cosmetic quality described - effect of thermal cycling found & monitored regularly - memory effects found for strong saturation (ongoing) - cross talk none was found - quality control monitoring provided on web 2. Mechanical & general performance - the shutter problem apparently fixed - shutter watch-dog "buzzing" device made - shutter timing accuracy TBD - vacuum oven for charcoal made (in use, needs refinement) - lid-opening in clean room done - wheel performance bearings exchanged, prepare for next time - HR-cam focus in slit plane TBD (by moving aperture wheel unit) - PTR vibration no effect down to 0.5" seeing (K) - alignment on telescope TBD (needs to be monitored) - pressure sensor exchange TBD (unreliable sensor) 3. Optical performance - Install focus pyramid TBD - WF plate scale 0.235"/pix in central 600x600 - WF optical distortion TBD (work started by Tapio) - HR plate scale TBD - HR optical distortion TBD - lateral colour distortion determined for WF - focus travel with wavelength determined for WF - PSF variations across FOV TBD (data taken for WF) - ghosts + scattered light reduced with HR mask, is small - filter quality check remains for most narrow-band filters - filter vignetting TBD for narrow-band filters 4. Sensitivity - photometric zeropoints found and monitored WF-cam - photometric scatter over FOV determined, very small - efficiency and throughput found 5. Observer's tools - User's Guide provided on web - General NOTCam documentation provided on web - Observing script generator provided on web - Exposure time calculator provided on web - Flat field archive provided on web - Quick look data reduction TBD - Reduction scripts mkflat.cl, std.cl (need refinement) 6. Software related - BIAS abort command TBD (CUO) - BIAS documentation TBD (CUO) - File storing options TBD (CUO) ?? - Individual wheel initialization TBD - Change to fits file extension TBD - FITS keywords improvement TBD --------------------------------------------------------------------------------- Practically all important results of the commissioning so far have been documented on our web pages in a short and user friendly form. Some tasks are still on-going (data available - time lacking ...) A document describing the commissioning more in detail has all the time been in preparation and will be finalized when the commissioning of the imaging mode can be regarded as terminated. I plan to submit a draft to participants of the commissioning (Graham, Jacob, Carlos, Pedro, John, Tapio and Thomas) who should be co-authors of the report, for comments and suggestions some time in April-May. The following tasks are still remaining: 1. Detector ------------ Basically all tasks have been performed. Most of these are now done by obtaining the detector monitoring data and feed them through the pipeline made by Silva. a) install the science array and redo all detector tests b) reduce the readout time from 3.6s to about 1s (new controller) 2. Mechanical & general performance ------------------------------------ a) determine the shutter timing accuracy and minimum safe exptime b) mechanical changes needed to bring HR camera to focus in slit plane c) test stability of array alignment vs. sky orientation (web instructions) d) exchange pressure sensor 3. Optical performance ----------------------- As an additional facility it was decided to add a focus pyramid to NOTCam. This work is in progress. At IJAF/CUO thermal cycling tests have already shown that the IR grade fused silica pieces cemented together can withstand strong cycling. The design of the pyramid is made by Michael Andersen, and the pyramid has now been ordered. a) install and test the focus pyramid, add needed software b) determine plate scale and distortion both cameras c) determine PSF variation across FOV (work started) d) find vignetting for narrow-band filters (see web instructions) 4. Sensitivity -------------- a) determine the photometric zeropoints also for the HR camera (JHKs) b) determine photometric scatter across FOV for HR cam c) throughput for narrow-band filters 5. Observer's tools ------------------- a) Provide some quick look data reduction tools 6. Software related ------------------- a) Provide a working BIAS abort command b) Provide some BIAS documentation c) Improve file storing options d) Allow for individual wheel initialization in the UIF e) Change format from fits cubes to fits file extension f) Improve and correct FITS header keywords ---------------------------------------------------------------------- What needs to be completed before giving final acceptance of NOTCam towards IJAF/CUO are: 1b) reduce the readout time from 3.6s to specs (new controller) 6a) Provide a working BIAS abort command 6b) Some short BIAS documentation ---------------------------------------------------------------------- In my opinion, what should be completed before considering the imaging mode of NOTCam as commissioned, are the following tasks: 2a) determine the shutter timing accuracy and minimum safe exptime 3d) find vignetting for narrow-band filters (at least one, see web instructions) 4a) determine the JHKs zeropoints also for the HR camera (ongoing) ---------------------------------------------------------------------- The optical performance in terms of plate scale solution and distortion maps together with PSF variations across the FOV, were originally in my plan for the commissioning. As distortion is a common phenomenon in IR cameras, it would be nice to have this mapped one day, but I consider it not necessary for the commissioning to be completed. Although they concern general performance of the instrument, steps 2b) and 2c) are only crucial for the spectroscopic mode. I haven't here included steps that need to be taken especially for the spectroscopic mode (like providing slit acquisition & dithering software or throughput for spectroscopic mode). ----------------------------------------------------------------------- Anlaug Amanda Djupvik 1st of April 2004